Sterilization containers with permanent filters made of a plastics material, in particular polytetrafluoroethylene, are known for example from DE 298 19 825 U1. They are used instead of conventional disposable filters, in particular paper filters, in sterilization containers to close gas exchange orifices. Although such plastics filters meet the requirements of porosity and pore size, they display weaknesses with regard to resterilizability.